At present, we have no idea how to do that, so the answer is still "this is not knowable" in practice.
Perhaps that changes tomorrow, or in a month, or a year from now, but until a theoretically-sound technique for understanding what the weights signify is described and demonstrated to be reliable, my statement remains true.
No, it’s not. It is unknown. To say it may be unknowable you need a fundamental reason why it may not be knowable.
What lies behind event horizons may be unknowable. We have theoretical reasons to suspect this. What LLMs are doing isn’t well enough understood, theoretically, to even say what is knowable versus unknowable. Just what is known and not.
A method not existing and a method being impossible (or unlikely) to exist are separate concepts. When you say something is unknowable, it should mean it literally cannot be known—route around the question entirely.
I had gotten my wires crossed and thought the OP was asking about a specific situation, but it was actually a question about the general pattern.
A specific situation will often pass before any theoretical tools can be found that could possibly answer the question.
For a general pattern, though, you're entirely right - if the tools arose hundreds of millions of years from now, that range of questions becomes answerable, and the information is then knowable.
Whether God exists is scientifically unknowable. The shape of a black-hole singularity is currently not known.
No, it’s not. Rumsfeld segregated what we know from what we know we know (and vice versa). An unknown (whether known or unknown) may be knowable or unknowable—his framework doesn’t address knowability.
> because an LLM is not a God. It is not an unknowable
I tend to agree with you. This has nothing to do with the Rumsfeld comparison being wrong.